Typically, when a traveling vehicle collides with a pedestrian, a bicycle, or a motorcycle, the pedestrian and the like usually get struck in the lower half of their respective bodies by a front portion of the vehicle body, to be tossed onto a hood which covers the front upper portion of the vehicle body, and then may secondarily collide with portions having a great rigidity such as pillar portions.
In Japanese Unexamined Application Publication No. 2000-264146, an externally-developed airbag device is disclosed for preventing a pedestrian and the like from directly colliding into A pillars by expanding an airbag along the left and right A pillars of the vehicle to protect the pedestrian and the like when the vehicle collides with the pedestrian and the like. Now, referring to FIGS. 11 and 12, this externally-developed airbag device will be explained. Further, FIG. 11 is a perspective view of a vehicle illustrating the airbag device for vehicle outer surface described by the above Publication, and FIG. 12 is a sectional view taken along a line XII—XII in FIG. 11.
The externally-developed airbag device described by the above Publication has an airbag 100 for being expanded along the vicinity of the circumferential edge portion of a windshield 113 of a vehicle 110.
The airbag 100 has a lower bag member 101 being expandable in the width direction (hereinafter, referred to as a left-right direction) of the vehicle body along a cowl top portion 111 and side bag members 102, 102 being expandable to be protruded in an upward direction along left and right A pillars 112, 112 of the vehicle 110 from both of the left and right ends of the lower bag member.
Between the side bag members 102, 102, a film 103 being unfoldable along the outer surface of the windshield 113 of the vehicle 110 in expanding the airbag 100 is provided.
In the inner space of the vehicle body on the rear-lower side of an engine hood 114 of the vehicle 110, a concave portion (not shown) for installing the airbag device is provided. The airbag 100 is normally received in the concave portion in its folded state, and is covered with the rear portion of the engine hood 114. In the concave portion, a gas generator (not shown) for inflating the airbag 100 is provided.
In a front bumper 115 of the vehicle 110, a sensor 116 for detecting a collision of the vehicle 110 with a pedestrian and the like is provided. If the sensor 116 detects the collision of the vehicle 110 with a pedestrian and the like, the gas generator starts by the detection signal to generate gas for inflating the airbag 100.
The airbag 100 starts expansion by means of gas from the gas generator and pushes up the rear portion of the engine hood 114 to be expanded toward outside of the vehicle body. Then, the lower bag member 101 is expanded in the width direction of the vehicle body along the cowl top portion 111, and in its left and right end sides the respective side bag members 102 are expanded in the upward direction along the respective left and right A pillars 112 to cover the A pillars 112.
Moreover, the film 103 is unfolded along the front surface of the windshield 113 in accordance with the expansion of the left and right side bag members 102, 102 to cover the windshield 113.
In this externally-developed airbag device, since the film 103 is unfolded to cover the whole windshield 113 when the airbag 100 is expanded, it is difficult for a driver of the vehicle 110 to visually detect the front side of the film 103. In the above Japanese Unexamined Patent Application Publication No. 2000-264146, it was attempted to secure the view of the driver by using a transparent material such as urethane in the film 103. However, different materials used for the airbag 100 and the film 103, respectively, increase the production cost while decreasing the manufacturing productivity. Further, if the film 103 is omitted, there is a possibility that the expanded side bag members 102 slip out to the sides of the vehicle.